嘗試使用菜單下拉菜單創建導航欄，但我的菜單項似乎不想顯示或它們隱藏在父容器中

Question

我正在創建一個想要響應的簡單導航欄。 我當前的問題是我試圖在一個菜單項上放置一個下拉菜單（從W3Schools中拉出），並且當我將鼠標懸停時，沒有任何菜單項出現，但是當我檢查它們時它們正在顯示。

我嘗試應用z-index並將位置更改為相對，但是沒有任何正常工作。

   <div class="navwrap">
      <div class="topnav" id="myTopnav">
         <a href="#home" class="active">Home</a>
         <a href="#news">News</a>
         <a href="#contact">Contact</a>
         <a href="#about">About</a>
         <a href="javascript:void(0);" class="icon" onclick="myFunction()">
            <i class="fa fa-bars"></i>
         </a>
         <div class="dropdown">
            <button class="dropbtn">Dropdown</button>
            <div class="dropdown-content">
               <a href="#">Link 1</a>
               <a href="#">Link 2</a>
               <a href="#">Link 3</a>
            </div>
         </div>
      </div>
   </div>

CSS

.navwrap{}
.topnav {
   overflow: hidden;
   background-color: #333;

   .dropdown {
      button.dropbtn {

      }
      .dropdown-content {}
   }
   .dropdown:hover .dropdown-content {
      display: block;
   }
 }

 .topnav a {
   float: left;
   display: block;
   color: #f2f2f2;
   text-align: center;
   padding: 14px 16px;
   text-decoration: none;
   font-size: 17px;
 }

 .topnav a:hover {
   background-color: #ddd;
   color: black;
 }

 .active {
   background-color: #4CAF50;
   color: white;
 }

 .topnav .icon {
   display: none;
 }

 @media screen and (max-width: 600px) {
   .topnav a:not(:first-child) {display: none;}
   .topnav a.icon {
     float: right;
     display: block;
   }
 }

 @media screen and (max-width: 600px) {
   .topnav.responsive {position: relative;}
   .topnav.responsive .icon {
     position: absolute;
     right: 0;
     top: 0;
   }
   .topnav.responsive a {
     float: none;
     display: block;
     text-align: left;
   }
 }
//Navigation Dropdown
.dropbtn {
   background-color: #4CAF50;
   color: white;
   padding: 16px;
   font-size: 16px;
   border: none;
}

.dropdown {
   position: relative;
   display: inline-block;
}

.dropdown-content {
   display: none;
   position: absolute;
   background-color: #f1f1f1;
   min-width: 160px;
   box-shadow: 0px 8px 16px 0px rgba(0, 0, 0, 0.2);
   z-index: 1;
}

.dropdown-content a {
   color: black;
   padding: 12px 16px;
   text-decoration: none;
   display: block;
}

.dropdown-content a:hover {
   background-color: #ddd;
}

.dropdown:hover .dropdown-content {
   display: block;
}

.dropdown:hover .dropbtn {
   background-color: #3e8e41;
}

JAVASCRIPT

function myFunction() {
    var x = document.getElementById("myTopnav");
    if (x.className === "topnav") {
      x.className += " responsive";
    } else {
      x.className = "topnav";
    }
  }

應該具有導航欄以及帶有下拉菜單的“下拉”菜單項。

 function myFunction() { var x = document.getElementById("myTopnav"); if (x.className === "topnav") { x.className += " responsive"; } else { x.className = "topnav"; } } 

 .navwrap {} .topnav { overflow: hidden; background-color: #333; .dropdown { button.dropbtn {} .dropdown-content {} } .dropdown:hover .dropdown-content { display: block; } } .topnav a { float: left; display: block; color: #f2f2f2; text-align: center; padding: 14px 16px; text-decoration: none; font-size: 17px; } .topnav a:hover { background-color: #ddd; color: black; } .active { background-color: #4CAF50; color: white; } .topnav .icon { display: none; } @media screen and (max-width: 600px) { .topnav a:not(:first-child) { display: none; } .topnav a.icon { float: right; display: block; } } @media screen and (max-width: 600px) { .topnav.responsive { position: relative; } .topnav.responsive .icon { position: absolute; right: 0; top: 0; } .topnav.responsive a { float: none; display: block; text-align: left; } } //Navigation Dropdown .dropbtn { background-color: #4CAF50; color: white; padding: 16px; font-size: 16px; border: none; } .dropdown { position: relative; display: inline-block; } .dropdown-content { display: none; position: absolute; background-color: #f1f1f1; min-width: 160px; box-shadow: 0px 8px 16px 0px rgba(0, 0, 0, 0.2); z-index: 1; } .dropdown-content a { color: black; padding: 12px 16px; text-decoration: none; display: block; } .dropdown-content a:hover { background-color: #ddd; } .dropdown:hover .dropdown-content { display: block; } .dropdown:hover .dropbtn { background-color: #3e8e41; } 

 <!-- NAVIGATION --> <div class="navwrap"> <div class="topnav" id="myTopnav"> <a href="#home" class="active">Home</a> <a href="#news">News</a> <a href="#contact">Contact</a> <a href="#about">About</a> <a href="javascript:void(0);" class="icon" onclick="myFunction()"> <i class="fa fa-bars"></i> </a> <div class="dropdown"> <button class="dropbtn">Dropdown</button> <div class="dropdown-content"> <a href="#">Link 1</a> <a href="#">Link 2</a> <a href="#">Link 3</a> </div> </div> </div> </div> 

Answer 1

overflow: hidden需要visible